Leigh’s family had long been resident in the Wigan area. His grandfather Alexander Leigh, an attorney, was legal and financial adviser to Sir Roger Bradshaigh of Haigh, Member for Wigan 1695-1747, was twice mayor and sometime town clerk and promoted the Douglas navigation which materially advanced the town’s prosperity. Hindley was bought during the 18th century, along with land at Billinge and Orrell, and Leigh himself rounded out his estates, said to be worth about £17,000 a year, with further purchases.
In 1800, his friends in Wigan corporation contrived to create enough new freemen to overthrow the controlling aristocratic s interests, and at the general election two years later he was returned unopposed with another local man. He was undisturbed in the seat until his retirement in 1820. A Pittite in politics, he voted for the orders of the day on Patten’s censure motion, 3 June 1803, and joined in the combined attack on Addington, 15 Mar., 23 and 25 Apr. 1804. He objected to the corn bill, 7 July 1804, arguing that it would hit Lancashire particularly hard with increased prices, and welcomed Hamilton’s amending bill, 1 July 1805. Otherwise he supported Pitt’s second ministry, voting against the censure of Melville, 8 Apr. 1805. He was a member of the committee on the 11th naval report, 27 May.
Leigh followed Canning in opposing the ‘Talents’. He voted against them on Ellenborough’s cabinet seat, 3 Mar.; the repeal of the Additional Force Act, 30 Apr. 1806, having been mustered by Canning (who described him as ‘a most flaming volunteer’ and ‘even without that additional stimulus’ likely to be ‘eager enough in his resistance to the overthrow of a favourite measure of Mr Pitt’);
Holt Lee [sic] was an honest fellow. Perceval said yes, but one who very willingly took [Canning’s] line. I answered not so, that I had known him long ... knew him to be very sturdy, and also knew it had cost him much pains to think of separating from [Perceval]; Canning’s exactions ... might perhaps revolt him, as [they] had done Bourne.
Ibid. Canning to his wife, 27 Nov. 1810; Phipps, Plumer Ward Mems. i. 364.
In July 1811 Canning reported that Leigh was ‘far away’ from Westminster and he failed to get him to come up for the debate on the orders in council, 3 Mar. 1812. At the end of the month he admitted that ‘of Holt Leigh I have heard nothing lately’, though he had just come to London and had ‘handsomely’ offered Canning his seat for Wigan if he could not find a berth at the next general election. He voted for a remodelling of administration, 21 May, and, on the peace preservation bill, 13 July 1812, joined in the chorus of protest at Brougham’s abuse of the magistracy. Before the election he was warned by Canning, who had refused the offer of Wigan because of his pro-Catholic views, to be on his guard against ministerial attacks.
He was duly listed as one of Canning’s 11 personal followers returned to the new Parliament and he voted with him on the sinecure bill, 29 Mar. 1813. When Canning drew up a memorandum of his friends’ claims on his junction with government in July 1814, he placed Leigh second in a list of five men for whom he wanted the offer of two baronetcies between them. He received the honour at the end of the year. At Canning’s suggestion it was granted with special remainder to his brothers, but in the event they predeceased him.
Leigh, a widely travelled and cultivated man, well versed in Greek literature, rebuilt Hindley Hall to his own designs but forgot to include a staircase. In his later years he had a notorious affair with Sarah Yates, the wife of one of his tenant farmers, to whose son Roger he left the reversion of his estates, which passed on a life interest to Leigh’s cousin Thomas Pemberton (later Lord Kingsdown), together with the interest on £20,000 as long as he remained a member of the Church of England.